Conditional inhibition of autophagy genes in adult Drosophila impairs immunity without compromising longevity.
Immune function declines with age in Drosophila and humans, and autophagy is implicated in immune function. In addition, autophagy genes are required for life span extension caused by reduced insulin/IGF1-like signaling and dietary restriction in Caenorhabditiselegans. To test if the autophagy pathway might be limiting for immunity and/or life span in adult Drosophila, the Geneswitch system was used to cause conditional inactivation of the autophagy genes Atg5, Atg7 and Atg12 by RNAi. Conditional inhibition of Atg genes in adult flies reduced lysotracker staining of adult tissues, and reduced resistance to injected Escherichia coli, as evidenced by increased bacterial titers and reduced fly survival. However, survival of uninjected flies was unaffected by Atg gene inactivation. The data indicate that Atg gene activity is required for normal immune function in adult flies, and suggest that neither autophagy nor immune function are limiting for adult life span under typical laboratory conditions.
Ren
Chunli
C
Molecular and Computational Biology Program, Department of Biological Sciences, University of Southern California, University Park, Los Angeles, CA 90089-2910, USA.
Finkel
Steven E
SE
Tower
John
J
D000375:Aging / Q000502:physiology; D000818:Animals; D030801:Animals, Genetically Modified; D001343:Autophagy / Q000235:genetics* / Q000502:physiology; D004330:Drosophila / Q000235:genetics* / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics* / Q000502:physiology; D004926:Escherichia coli / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000276:immunology; D005215:Fasting / Q000502:physiology; D005786:Gene Expression Regulation; D007109:Immunity / Q000235:genetics; D008136:Longevity / Q000235:genetics; D008297:Male; D013194:Staining and Labeling
D029721:Drosophila Proteins